1. Make sure you have the latest version of Desktop Manager installed. Currently, the latest version available is 4.3 and may be downloaded here: http://www.blackberry.com/go/softwaredownloads
2. Download the above file to the PC then install it to the PC by running the file you downloaded.
3. Locate the vendor.xml file and delete it. It is located at C:\Program Files\Common Files\Research in Motion\Apploader
4. Plug in the BlackBerry and open Desktop Manager. You should be prompted to upgrade.

The process takes about 45 minutes to an hour depending on how much data you have to backup and restore during the process. Once it's done loading the new OS it will reboot (it may do this twice during the entire process.) You will see a white screen with an hourglass for up to 20 minutes at a time while the DM says "waiting for initialization." Don't unplug from the PC & Don't remove the battery unless the spinning hourglass has been there for 30 minutes or more. If the hourglass has been spinning for more than 30 minutes continuously you will need to wipe the device with JL_Cmder (close out of Desktop Manager during this process.) You will then end up with a white screen with small icons and an error code number like 507 or 543.

I dont think these a reall updates but only particular for the provider service, but i could be wrong.

Well it installed perfect and put in all my 3rd apps no problem.
But i had some data isues and audio isues,
This is after i redid service books and more.
I always have 1XEV Never a data freeze or drop, but after the upgrade i got
1xev and NO data working till i turned the radio on and off, Next i had all sudden while on the fone with good signal a volume drop so low i could not hear the other person unless i restarted the dailing again, dont know if this is from the upgrade or conflict with other 3rd party software.

I did revert back to the old telus Firmware 76 my data dropped and froze to many times, never had that before.

I dl'd the file and installed it on my pc then started desktop 4.3 but it doesn't have anything to install...no os...where does it put it the file so i can put in my BB? sorry figured it out...i guess i can't follow directions

Is it me or this give more free memory after upgrading I went from .176 to this with out taking out preloaded pics I was booting up 19 megs free on the update the 176 I was booting 17.5 megs. With all the 3rd party stuff I have installed. Just seems to me I gained about 2 megs free.

well im trying again, i have more conections isues with the old 176. I think maybe the area had a bad day. I use to have BELL 79 firmware nad was stunning. thougth i upgrade to later one. With other words im trying it again one more time and delete and reset the service books thats all.